How is relative dating used to evaluate geologic time
Igneous rocks includes intrusive rocks (rocks that cooled below the surface) and volcanic rocks formed on the Earth's surface by volcanism.
Igneous rocks also form from melting associated with extraterrestrial impacts.
One of the products of this collective investigation over time is the geologic time scale (Figure 3-2).
It is important to note that tectonic forces within the Earth are responsible for many of the changes to rocks and surface features on the landscape.
Tectonic forces are responsible for the gradual uplift of mountain ranges, both on land and on the seafloor, as well as creating basins that flood with lakes or seawater, and fill in with sediments (Figure 3-5).
Geologists use geochronology — the study of the age of rocks, using both absolute dating methods and relative dating methods.
The second half of this chapter focuses on maps and the display of geographic and geologic information in two-dimensional and three-dimensional formats.